Unfortunately I only ended up getting a single day this weekend on the engine, but I suppose thats life! First up was to build up the crank. Again all this is like normal, and the rod bolts seemed pretty consistent, which is a relief!!! There are two methods of tightening rod bolts. You can either just do them up to a specific torque, or you can stretch them a certain amount. Stretching them gives a more accurate result, but takes a bot longer as you have to measure them before, and then a few times whilst tightening them up, but I decided to use the stretch method as it gives a better result.
So after much measuring the small incremental torque adjustments the crank was built up.
The next job was to strip, clean, inspect and rebuild the gearbox. Again here, the haynes manual was just the ticket. Although if i had had to think about it stripping the two shafts is not exactly hard, but the manual was so much quicker doing it for the first time!
Then it was time to drop the two gearbox shafts and crank into the UPPER crankcase, stick the gears into neutral, as well as the selector mechanism, and stick the two halves together.
It was then a little bit frantic, as I was not quite sure if I had done up all the bolts, as I have not built one of these before, and as ever there are less obvious bolts hiding around the place, but luckily enough I got them all in first time, otherwise the sealant goes off and you have to split the cases and start again.
I wanted to get the sump pan on, mainly it seals the engine up a bit but secondly it gives it a flat base to stand it up on. Therefore the next part to go on was the balancer shaft. Again here the haynes manual was invaluable! It not difficult to do, but the manual shows exactly where all the timing marks are, so you dont have to route around looking for them on all the different covers! So after that was bolted in it was on with the sump pan. I have to admit at this point i thought i was starting to make a bit of progress! Then the gearbox selector cover, dry sump pump and pipes.
Next up, as I have had new pistons made, Iwanted to do a compression ratio check. This is not too tricky a thing to do, but of course you have to be very accurate or the result will be wildly wrong. To do it I use a burette filled with WD40, and smear the piston edges with a little grease, making sure not to get any on top of the piston or the measured volume will be inaccurate! Below is a stunning picture of Richard about to attack the engine with a dollop of grease! I did the volume check 3 times. The first time I got a sensible number, but not the second. I thought i had a leak, but the volume didnt seem to be lowering… Somewhat concerning… Then I realised the engine was not on TDC, I must have knocked it and rotated the engine whilst getting it absolutely level, so any air bubbles escaped up the plug hole. This leveling was a bit of a worry as the engine had to be balanced with the sump pan half falling through the work mate, so Iam sure that is how it happened. But well nevermind, thats what checking is for!!! So onto a third check and this time I got the same volume as the first go, and so I was happy I had it right! Obviously it is important to not get any leaks when doing this, or any air bubbles, hence doing it more than once is quite important.
Tags: Engine
